HELP PLEASE... Installing travertine over backer board

Please help ASAP. I am getting conflicting information. The more I research and ask around, the more answers I get. I am having travertine installed in less than a week and I am stuck on preparing the subfloor. I am trying to do myself to save money. I am female but have a couple of strong teenage boys to help out.

I removed old ceramic tile from the second level of my 28 year old home and also removed the backer board as it was getting nicked up in the removal process. The 1/2 inch plywood did need to be replaced in a few places. My problem is what to do next. I've purchased 1/2" Hardie Board and thinset/screws to adhere the boards with, but conflicting information as to the thickness needed for travertine and whether or not I need to use thinset. I want to do best possible job.

I have now just been told don't lay travertine over cement backer board and switch to porcelain as travertine only is good when applied to solid cement. Also, stated travertine hard to clean.

Please help...

Thanks Lori

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HELP PLEASE... Installing travertine over backer board

How thick is the subfloor? I know you said you repaired some of the 1/2", but is there something thicker under it?
Just 1/2" as a subfloor is not thick enough for any flooring.
Travertine is a brittle very porous tile and is hard to clean and easy to stain.
Porcelain or ceramic would be a much better choice.
Thin set needed to be used under the tile board or the tiles going to crack.
Thin set should always be used to set the tile.

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HELP PLEASE... Installing travertine over backer board

The plywood is attached to the joists?? It is 2nd level of home. Had ceramic tile already there that I took up. The hardie board is 1/2" so that will be a combined 1" subfloor. Is this not enough for travertine? I am installing in my foyer, hall, kitchen and dining room.

HELP PLEASE... Installing travertine over backer board

1/2 subfloor would not even be expectable to todays code for any flooring.
Way to much flex.
Should have been 3/4" tonged and grooved then a layer of at least 3/8 underlayment rated plywood then 1/4 tile board.
Also the size of the floor joist should have been taken into consideration.

HELP PLEASE... Installing travertine over backer board

Natural stone is beautiful but requires more maintenance and also a much stiffer subfloor system. Most homes are not built to meet the requirements for stone unless it was to be installed when built.

We need to start with the joists. Tell us their type & size, spacing and unsupported span to the inch. Also try to determine their species and grade. Since this is the second level I know you may not be able to see the joists. But they probably used the same throughout the home, so look elsewhere. You can determine the height (2x10 - 2x8) by drilling a small hole in the subfloor and sticking a stiff wire or wooden dowel down until it hits the ceiling below, then do the math.

It's surprising your subfloor is 1/2", are you positive? If it is only 1/2" was there ever another layer over it that was removed during a remodel?

We'll talk more about the next step once you answer these Q's.

Quote:

Originally Posted by Lwentwo

Please help ASAP. I am getting conflicting information. The more I research and ask around, the more answers I get.

The internet is a fantastic thing, but there's so much bad advice there too. You will get the best advice here, I guarantee it.

HELP PLEASE... Installing travertine over backer board

Thanks for the great response. CORRECTION Plywood floor is .668" and the joists are 2X8 16''. centers. The only subfloor that I know of is the existing 1/2 inch plywood. It did have backerboard with ceramic tile but I removed that this week. There was some bad wood that I replaced this week as well but there is definitely some flex. I've contacted the travertine installer to lay the backerboard and he gave me a decent price. He thinks the subfloor is fine but I am concerned as he is more of a carpet guy than tile as he is not doing the work himself. I live in the Tampa Bay area of Florida. There is a crawl space that is dirt underneath that is about 4 feet down from subfloor.

I also should've mentioned when I bought home 9 years ago they owner did disclose termite damage in foyer. I knew there would be some problems as the ceramic and grout was coming up. Hence, the remodel.

HELP PLEASE... Installing travertine over backer board

So, you added that the corrected thickness is .668, but didn't erase the 1/2" part. Are you trying to confuse us?

You measured .668 with calipers? That's more than 5/8", what's up? Now I don't know what you've got there. It might very well be 3/4", or maybe the ply has swelled in that area. Plywood is generally 1/32" thinner than its stated size. So 3/4" might measure .710 ish. You tell me. Crawl under there and read the stampings.

What I do know is that your carpet layer needs to stay away from a travertine tile installation, and that goes for his friends too. Anyone who thinks a single layer of ply, (even if it is 3/4"), with concrete backer over it is good enough for stone has no clue.

Quote:

he gave me a decent price.

When a customer says "he gave me a decent price", it means he gave you a fantastic price which is too low to be a good deal. Too cheap usually costs too much in the end. Doing it again in a few years is not cost effective.

You need to find someone else, someone that is expert in tile & stone over suspended wood floors.

You missed this?

Quote:

Originally Posted by Jaz

Tell us their type & size, spacing and unsupported span to the inch. Also try to determine their species and grade.

HELP PLEASE... Installing travertine over backer board

The stamping on ply says .688. The distance from foundation to cross beam is 13'. The "carpet" guy who came out to give estimate is the owner of the store and like most carpet stores here in my area, also sells stone/tile. He doesn't do the actual labor himself. I have about 300'of area to be tiled. The travertine and install is $3300.00 of which I don't know how much is the stone versus the labor. The cost to install the cement board is $975. this includes the material and warranty. He wouldn't use the material I already purchased and give warranty., so I will return mine to Home Depot. I thought this was a good price but I guess I really don't know.

So, what do you suggest? I want the best possible job as you are correct, I don't want to have issues. So, I am willing to spend whatever amount necessary at this point.

HELP PLEASE... Installing travertine over backer board

OK, let's start with the framing, that's always first. For natural stone both the joists and subfloor need to meet or exceed a deflection rating of L720. This is equal to 1/720 or 1 inch in 720 inch or any fraction thereof. For ceramic the max deflection is L360, which is also what modern building codes call for in residential. So, two deflections, one for the joists and another for the layers of ply.

In addition, natural stone requires a double layer of subfloor sheathing, which is kinda redundant since I don't know of any single sheet that would give you the rating in the first place.

Let's look at your joists. 2x8 of unknown species and grade, 16" oc, span 13' 0". Your joists come in at under L250. It's not even a good idea for regular ceramic.

To safely continue with the travertine idea in regards to the joists, first you'd have to either sister all the joists, or shorten the span to about 8' or less.

As for the .688 ply, you need to add another 1/2" underlayment grade ply, then install the concrete backer or a membrane such as Ditra.

HELP PLEASE... Installing travertine over backer board

Thanks for all the help I've recieved here. I am going to look at having something other than travertine installed as the issue with having to put so much work into strengthening the joists is much more than I bargained for.

My installer has told me if I back out I will lose almost $500 as a restocking fee if I dont proceed but I will deal with that now

HELP PLEASE... Installing travertine over backer board

Well, sorry to hear about the current situation and the bad info this contractor gave you. I don't imagine you told him to continue with the work even though the specs and his proposed method does not meet minimum industry standards.

However, back to your joists. Based on the info I have your floor is rated for vinyl, and carpeting. I suspected the numbers may not be accurate, and knowing the species and grade might change the specs for ceramic.

You found the stampings on the plywood. The joists also have stampings telling you what they are.

HELP PLEASE... Installing travertine over backer board

Your installer/seller has given you some bad information and sold you a product that is not suitable for the application. Your installer/seller may be in the business but please don't think that he is qualified to do what he is doing - he is not.

He should have investigated your structural criteria long before selling you travertine. If he knew what he was doing he wouldn't be suggesting or agreeing to travertine for your installation.

For him to try to salvage a bad-sale created by his ignorance of the business by saying he will keep your five-hundred dollars is actually an actionable offense on his part and if this occurs you could easily sue him in small claims court and get your money returned to you. I suggest you get away from this guy, cancel the sale to mitigate your damages and chase your money later if he keeps it. Find a different installer/seller that knows the business and knows the meaning of the word "honesty".

In the meantime listen to what JazMan is telling you, he is a true expert in this field.

HELP PLEASE... Installing travertine over backer board

Hi Bud, Thanks for your help in this. BTW, we ALL miss you.

Lwentwo,

If you need advice and/or a very good tile setter to do the work let me know. I know of a guy in your area and I might be able to get him to call you or better yet you call him. If I remember he's in the Tampa area, same as you.